Strapping tool



J. E. DIMMETT STRAPPING TOOL Feb. 1, 1966 Filed Jan. 4, 1963 INVENTOR JAMES E DIMMETT ATTORNEYS United States Patent 3,232,323 STRAPPENG TUGL James E. Dimrnett, South Glastonbury, Conn., assignmto The Stanley Works, New Britain, Conn, a corporation of Connecticut Filed Jan. 4, 1963, Ser. No. 249,502 2 Claims. (Cl. Mil-93.4)

This invention relates to an improved strapping tool for tensioning straps about packages, boxes, and the like and for securing the overlapped ends of the straps together while in a tensioned state.

One of the objects of the present invention is to provide an improved strapping tool that will tightly secure strapping around packages of various sizes and shapes and that may be easily removed from the strapping and package at the completion of the sealing operation. Ineluded in this object is the provision of a novel strap raiser which will space from the package by a uniform distance the overlapped strap portions to be secured together regardless of the shape or size of the package.

A further object of the present invention is to provide such an improved strapping tool having incorporated therein a novel strap raiser that will effectively space the overlapped strap portions from the package as well as properly position the same so as to highly facilitate the sealing operation as well as to provide an improved strapping securement of the package. Included in this object is a provision of such a novel strap raiser that will self-adjust to various package sizes and shapes and that will properly position the seal in the tool so as to' permit the seal to be applied to the strapping to obtain an effective strap joint.

A still further object of the present invention is to provide such a novel strap raiser that is extremely economical to manufacture and that may be easily attached to conventional strapping tools prior or subsequent to assembly thereof and whereon it will effectively operate over long periods of repeated and rugged use.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application which will be indicated in the appended claims.

In the drawings:

FIG. 1 is an elevational view of a strapping tool incorporating the present invention and shown mounted on a package or the like and in seal-applying position;

FIG. 2 is a fragmental perspective view of a portion of the strapping tool shown together with overlapped strap portions that have been scaled thereby;

FIG. 3 is a fragmental cross-sectional view taken generally along line 33 of FIG. 1; and

FIG. 4 is an exploded perspective view of a strap raiser utilized in the present invention.

Referring to the drawings in detail, the present invention is shown incorporated in a strapping tool generally designated 2 which is shown in FIG. 1 as applying a seal 4 to overlapped end portions 6 and 8 of a strap to secure the strap about a package 10 illustrated as having a circular cross section. The strapping tool 2, shown for illustrative purposes only, is of a well-known type including a strap tensioning means generally designated 12, a strap sealing means generally designated 14, and a seal feeding means generally designated 16.

The strap tensioning means 12 includes a gripping wheel 18 which has peripheral serrations or teeth 19 and is suitably mounted for rotation on the body of the tensioner 2; and a foot 20 formed on the base of the tensioner 3,232,323 Patented F eh. I, 1966 body in underlying relationship to the gripping wheel 18 as shown in FIG. 2. The gripping wheel 18 and the foot Zil are spaced apart sufficiently to receive the overlapped strap portions 6, 3 therebetween and so that upon rotation of the "ripping wheel 18, the teeth 19 will engage strap portion 8 to move strap portion 8 longitudinally relative to strap portion 6 thereby to apply tension to the strap in a conventional manner. It will be noted that foot 20 is provided with a plug 21 having a knurled surface or teeth to grip strap portion 6 to prevent its longitudinal movement. The plug is threaded for vertical adjustment to accommodate strapping of different thickness. Rotation of the gripping Wheel 18 is effected through means of the lever 22 which is suitably connected to the gripping wheel 18 such as by a ratchet means (not shown). At one side of the foot 20 there is formed on the tool body a guide surface 24 adapted to engage the side edge of the strap 5 as shown in FIG. 2 to thereby properly locate the same for the tensioning and sealing thereof.

The sealing means 14- includes a head 26 adapted to receive the seal 4 therein as shown in FIG. 3 and a pair of sealing jaws 2 8 pivotally mounted in the head 26 and adapted to clamp the seals 4 to the overlapped strap portions 6 and 8 in a conventional manner to thereby form the strap joint. Actuation of the sealing jaws 28 is accomplished through means of the lever 30 pivotally mounted at 32 and which is suitably connected to the sealing head 26 to raise or lower the same upon pivotal movement of the lever iii In FIG. 1 the sealing lever 3G is shown in its lowermost position wherein it has lowerecl the sealing head 26 to actuate jaws 28 to thereby clamp the seal 4 about the overlapped strap portions 6, 3. A more detailed description of the structure and operation of the sealing head 26, jaws 23, and the connection of lever 39 to the sealing head 26 may be found in the United States Patents Nos. 2,218,023 and 2,524,654.

The seal feeding means 16 includes a magazine 33 adapted to receive a stack of seals 4 and a spring biased lever 34 connected to a suitable feeding member (not shown) and adapted to advance the seal 4 between the jaws 28 of the sealing head 26 when the sealing head is raised to its uppermost position by the sealing lever 30. Actuation of the seal feeding lever 34 is also effected by the movement of sealing lever 34 during the initial portion of the sealing operation. A more detailed description of the structure and operation of the seal feeding means 16 may be found in the above-cited patents.

\Vith strapping tools such as of the above-described type, because of the tension applied to the strap 5 which is effective to draw the strap 5 towards the surface of the package it), it has been found necessary in the past to provide a block or the like for raising or spacing the overlapped strap portions 6, 8 from the package 10 so as to permit the strap portions 6, S to be received in the sealing head 26 for the sealing operation. However, since such blocks were not adjustable to various package sizes and shapes, the result was that, when the block was removed from between the strapping and the package after the sealing operation, the tension on the sealed strapping was not uniform as between packages of different sizes and shapes.

In accordance with the invention, there is incorporated in the improved strapping tool, a novel strap raiser or spacer generally designated 40 comprising a generally planar base member 41 formed from a suitable flexible and resilient sheet material such as spring steel and having one end suitably fixed to the under surface 42 of the tensioner foot 20 as by means of the screws 44 shown in FIG. 4. In the illustrated embodiment, the other end 46 of the base member 41 is raised by rolling it back on itself, to provide a transversely extending passage 48 adapted to receive a cylindrical cross support member 50 in the manner as best shown in FiG. 4. One end of the cross support member 50 is provided with an integral guide flange 52 while the other end is provided with a threaded passage 54 adapted to receive the screw 56 for securing the cross member 50 to the strap raiser through means of the engagement of the screw head 58 and the guide flange 52 with the opposite ends of the raised portion 46 respectively, as shown in FIG. 2. If desired, a washer such as 60 may be employed between the screw head 58 and the strap raiser as shown in FIG. 4.

The guide flange 52 is constructed and arranged such that its inner face 62 is in alignment with the guide face 24 of the tool described above so as to engage the side edge of the strap in the same manner as shown in FIG. 2 to thereby locate the proper position of the strap for the sealing operation. The raised end portion 46 of the strap raiser is spaced from the end 25 of the tensioning foot 20 so as to provide sufficient space for the sealing head 26 to receive the overlapped strap portions 6, 8 as shown in FIG. 1.

In a strapping operation, the overlapped strap portions 6, 8 are placed over the strap raiser 40 and between the gripping wheel 18 and foot 29 with the guide surfaces 24, 62 being employed to locate the proper position of the strap portions for tensioning and sealing thereof. Tension is then applied to the strap 5 by the tensioning means 12, which causes the strap 5 to engage the raised end portion 46 of the strap raiser to move the latter towards the package and into engagement therewith whereby the base member 41 will conform to the surface of the package 10 as shown in FIG. 1. In this tensioned position of the strap 5, the overlapped portions 6, 8 thereof will be spaced from the package 10 by the raiser portion 46 a uniform and limited distance above the package so as to permit the sealing head 26 to be properly applied thereto as well as to leave the strap 5 tightly bound about the package 10 when the strapping tool is removed at the completion of the sealing operation.

The sealing head 26 is then brought downwardly to receive the overlapped strap portions 6, 8 as shown in FIG. 1, and to clamp the seal 4 thereabout to complete the strap joint. The strapping tool 2 is then removed and this may be highly facilitated by pivoting the tool about either of the guide faces 24 or 62, respectively, in a direction transverse to the strapping.

It will be noted that when the strapping tool 2 is employed to strap a package whose surface has, for example, a lesser radius of curvature than the package 10, the strap raiser 40 will undergo a greater deflection to adjust to this condition so as to provide a uniform and limited space for accommodating the sealing head 26 and for permitting the strapping to be tightly bound on the package when the tool is removed. It has been found that the strapping tool of the shown embodiment will successfully strap packages having radius of curvatures ranging from six inches to infinity.

The guide flange 52 of the strap raiser 4% is additionally provided with an inclined cam surface 63 dimensioned and positioned such that should the seal 4 be projecting from the ends of the sealing head 26 (in the left-hand 4 direction as viewed in the drawings) the cam surface 63 Will engage the end of the seal 4- as the sealing head 26 is moving to scaling position whereby the seal will be pushed into its proper longitudinal position in the sealing head for the sealing operation.

From the above, it will be seen that the present invention not only highly facilitates many phases of the strapping operation but also insures that the strapping will be applied to the package in an extremely secure and uniform manner regardless of the size or curvature of the package.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.

I claim:

1. In combination with a strapping tool having a base with an upper knurled face for receiving overlapping portions of a loop of strappin encircling an article and a first guide edge adjacent said knurled face engageable with the edges of the overlapping portions of strapping, a strap tensioner for clamping the overlapping portions of strapping against the knurled face of the base and for forwardly advancing the outer overlapping portion of strapping to tension the loop about the article, and a strap sealing head rearwardly of the base pivotal between a retracted position and an extended position for applying a strap seal onto the overlying portions of the loop of strapping, a strap raiser comprising a resilient cantilever band having a forward end fixed to the base and a free end positioned rearwardly of the strap sealing head, and an upstanding support at the rear end of the resilient cantilever band engageable with the underside of the loop of strapping for raising the loop above the article for sealing, said support having a second guide edge in alignment with the base guide edge and cooperative therewith for aligning the overlapping portions of the loop of strapping for sealing and a forwardly facing cam edge adapted for engagement with a seal supported in the sealing head to ensure that it is positioned between the base and the support as the strap sealing head is pivoted to its extended position.

2. In the combination of claim 1 wherein the upstanding support is provided by a rolled inturned rear end of the cantilever band and a member fixed within the inturned rear end having a side flange providing said second guide edge and said forwardly facing cam edge.

References Cited by the Examiner FOREIGN PATENTS 145,585 3/ 1952 Australia. 498,268 5/ 1930 Germany. 506,266 9/1930 Germany. 609,841 2/ 1930 Germany. 816,076 10/ 1951 Germany. 744,101 2/ 1956 Great Britain.

CHARLES W. LANHAM, Primary Examiner.

WILLLAM J. STEPHENSON, Examiner. 

1. IN COMBINATION WITH A STRAPPING TOOL HAVING A BASE WITH AN UPPER KNURLED FACE FOR RECEIVING OVERLAPPING PORTIONS OF A LOOP OF STRAPPING ENCIRCLING AN ARTICLE AND A FIRST GUIDE EDGE ADJACENT SAID KNURLED FACE ENGAGEABLE WITH THE EDGES OF THE OVERLAPPING PORTIONS OF STRAPPING, A STRAP TENSIONER FOR CLAMPING THE OVERLAPPING PORTIONS OF STRAPPING AGAINST THE KNURLED FACE OF THE BASE AND FOR FORWARDLY ADVANCING THE OUTER OVERLAPPING PORTION OF STRAPPING TO TENSION THE LOOP ABOUT THE ARTICLE, AND A STRAP SEALING HEAD REARWARDLY OF THE BASE PIVOTAL BETWEEN A RETRACTED POSITION AND AN EXTENDED POSITION FOR APPLYING A STRAP SEAL ONTO THE OVERLYING PORTIONS OF THE LOOP OF STRAPPING, A STRAP RAISER COMPRISING A RESILIENT CANTILEVER BAND HAVING A FORWARD END FIXED TO THE BASE AND A FREE END POSITIONED REARWARDLY OF THE STRAP SEALING HEAD, AND AN UPSTANDING SUPPORT AT THE REAR END OF THE RESILIENT CANTILEVER BAND ENGAGEABLE WITH THE UNDERSIDE OF THE LOOP OF STRAPPING FOR RAISING THE LOOP ABOVE THE ARTICLE FOR SEALING, SAID SUPPORT HAVING A SECOND GUIDE EDGE IN ALIGNMENT WITH THE BASE GUIDE EDGE AND COOPERATIVE THEREWITH FOR ALIGNING THE OVERLAPPING PORTIONS OF THE LOOP OF STRAPPING FOR SEALING AND FORWARDLY FACING CAM EDGE ADAPTED FOR ENGAGEMENT WITH A SEAL SUPPORTED IN THE SEALING HEAD TO ENSURE THAT IT IS POSITIONED BETWEEN THE BASE AND THE SUPPORT AS THE STRAP SEALING HEAD IS PIVOTED TO ITS EXTENDED POSITION. 